Shock train generated turbulence inside a nozzle with a small opening angle

Shock train generated turbulence inside a nozzle with a small opening angle
Grzona, A.; Olivier, H.
2011-04-02 00:00:00
The flow inside an over expanding rectangular nozzle with a small opening angle of 1.6° is investigated by means of high-speed schlieren and shadowgraph photography, pressure probes and hot-wire anemometry on the nozzle centre line in order to measure the turbulent fluctuations generated by the occurring shock wave/boundary layer interaction. Additionally, an optical shock capturing tool is deployed to measure the amplitude and frequency of the shock train oscillation. Varying the back pressure, the pre-shock Mach number is changed between Ma
1 = 1.1 and 2.1. Two different modes of turbulence generation and distribution are detected. For a single normal shock and a normal shock train, the normal Reynolds stress
$$ \overline{{u^{\prime 2} }} $$
on the channel axis is only slightly increased compared to the free stream value, whereas for the cases of a lambda foot shock train and an x-type shock train, a strong intensification by forming a turbulent mixing zone can be observed.
http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.pngExperiments in FluidsSpringer Journalshttp://www.deepdyve.com/lp/springer-journals/shock-train-generated-turbulence-inside-a-nozzle-with-a-small-opening-9U8yFiKmV3

Shock train generated turbulence inside a nozzle with a small opening angle